There were bizarre scenes at the Canadian Open on Thursday morning (AEST), with a highly unusual moment forcing the umpire to overturn his decision.

During the second round match between Gabriel Diallo and Matteo Gigante, the latter called for a review while on serve after claiming his rival’s return went through the net.

Gigante attempted to explain his version of events and the umpire obliged, sending it through to a video review.

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After multiple replays, it was clear that Diallo’s shot had indeed gone through the net, which is an incredibly rare occurrence at the professional level.

Matteo Gigante explains to the chair umpire Twitter

The crowd in Montreal reacted to the footage with disbelief, gasping each time it was shown, before the chair umpire confirmed what had happened and overturned the point.

The strange moment was only a bump in the road for Diallo however, who went on to win a tight match 6-3, 7-6(5) on home soil to advance to the next round.

Elsewhere at the event, Alex de Minaur continued his strong run of form with a straight-sets win over Francisco Comesana, while fellow Aussie star Chris O’Connell caused an upset against Stefanos Tsitsipas in three sets.